A biopsy is a procedure to remove tissue from a patient for diagnostic examination that may involve taking a tissue sample and/or body fluid from a patient. Tests performed on the resulting tissue specimen can provide information for diagnosis of the patient's condition.
Biopsy samples have been obtained in a variety of ways in various medical procedures using a variety of devices. Biopsy devices may be used under stereotactic guidance, ultrasound guidance, magnetic resonance imaging (MRI) guidance, or otherwise. Exemplary biopsy devices include, without limitation, needle-based biopsy guns: for example, vacuum-assisted biopsy devices, fine needle aspiration biopsy devices (FNAB), and core needle biopsy devices; disposable and reusable biopsy needles; and biopsy forceps: general biopsy forceps and hot biopsy forceps, etc.
A biopsy may be obtained by an open or percutaneous technique. Open biopsy typically is an invasive surgical procedure which removes an entire mass or a part of the mass after an excision (denoting surgical removal of part or all of a structure)/incision (denoting surgical wound; a division of the soft parts usually made with a knife) is made. Percutaneous (denoting the passage of substances through unbroken skin and passage through the skin by needle puncture) biopsy is less invasive and usually is done with a needle-like instrument to collect a biopsy sample, for example, a fine needle aspiration (FNA) or a core biopsy. A FNA biopsy, which normally can be obtained for cytologic examination, generally includes individual cells or clusters of cells without preserving the histological architecture of the tissue cells. A core biopsy is a biopsy obtained for histologic examination in which a cylindrical sample of tissue is obtained using a hollow needle. The type of biopsy tools to be used depends on the circumstances. Typically, a core biopsy is used more frequently by the medical profession.
Methods and apparati for automated biopsy and collection of soft tissue are known. Many are cumbersome and not intended for disposable use. Methods that employ a vacuum chamber cannula to draw tissue into a receiving port where the vacuum chamber defines at least one, usually multiple, communicating holes between the chamber and the outer cannula, for example, are problematic in that these small holes often become clogged with blood and bodily fluids, such that the fluids occlude the holes and prevent the aspiration from drawing the tissue into the receiving port. This ultimately prevents a core from being obtained, a condition called a “dry tap.” In addition, because many of the components of current biopsy devices are reusable, such as the driver portions, which control the outer and inner cutter needles, this can pose several disadvantages, for example, (1) the reusable portion must be cleaned and/or sterilized, which increases the time necessary to wrap up the procedure, which ultimately affects the cost of the procedure; (2) the required clean-up and/or sterilization of reusable parts increases the staffs' potential exposure to body tissues and fluids; (3) the reusable handle is heavy, large and cumbersome for handheld use.
A variety of biopsy needles and guns have been described and used for obtaining tissue specimens. In biopsy needles and guns that employ a manual vacuum generation mechanism, the mechanism often is complex, cumbersome, potentially expensive, and not disposable.
Most currently available biopsy devices involve complex mechanism, and thus are not intended to be disposable. Some of them rely on electric power to drive the motors for cutting and to establish a vacuum. Although some of the automated or manually actuated biopsy guns contain a disposable needle (stylus or cannula), replacing the disposable stylus or cannula can be troublesome and can pose a potential danger because this action exposes persons handling the needles to danger of infection. Also, in case the tissue touches other parts of the device, it could also expose the next patient or the medical professional to a potential health hazard.
In light of the foregoing disadvantages, a need exists for a disposable vacuum-assisted biopsy device which is simple, lightweight, portable, and cost effective to manufacture and dispose of.